NEW YORK – The collapse of a deal with the former Chrysler Group LLC for a fullsize pickup derived from the Dodge Ram hasn’t dampened Nissan Motor Co. Ltd.’s enthusiasm for a new-generation Titan.

Nor has it discouraged Nissan from wanting to build a medium-duty, diesel-powered Titan.

“We are going into commercial vehicles in North America; it is a good profitable segment and you need to have trucks,” Tom Lane, corporate vice president of product planning and strategy, tells Ward’s in an interview here.

Nissan recently unveiled its first foray into the U.S. commercial-vehicle market, the fullsize NV van that goes on sale later this year and is based on an updated version of the Titan’s F-Alpha platform.

With no other prospective partners in sight, the Japanese auto maker already has said it intends to go it alone with the next-generation Titan. The current pickup debuted in 2003 as an ’04 model.

Chrysler was to build a Nissan-designed, Ram-based Titan beginning in 2011, but that deal was nixed following the auto maker’s bankruptcy and eventual takeover of management control by Fiat Automobile SpA.

It’s unclear if a heavy-duty version of the Titan was part of the pact.

Only the Detroit Three offer diesel-powered, medium-duty (marketed as “heavy-duty”), pickups.

The best seller of the bunch is Ford Motor Co.’s Super Duty line, comprised of the F-250, F-350, F-450 and F-550 models.

Current Titan bowed in 2003.

Ward’s data shows Ford delivered 21,115 medium-duty F-Series pickups in the U.S. last year, a 45.9% decline from 39,044 in 2009.

U.S. fullsize pickup sales have shrunk dramatically in recent years, as the slowdown in the housing sector took a bite out of the commercial-use market.

Still, with projections for volumes to bounce back to the 2-million-unit mark by 2015, a level not seen since 2007 and well above 2009’s 1.1 million, Lane believes it makes sense to maintain a market presence.

“It’s a huge, huge segment…so we’re here,” he says. “We have a commitment to make commercial vehicles and trucks work.”

But to do that, Nissan will be faced with the considerable task of developing a competitive medium-duty pickup.